Recently, as a new type of semiconductor light emitting device (LED) technology, semiconductor light emitting devices including nanostructures have been developed. In such a semiconductor light emitting device including nanostructures (hereinafter, referred to as “a nanostructure semiconductor light emitting device”), an active layer can be grown on a non-polar plane or a semi-polar plane, preventing degradations in device efficiency due to polarization. Also, since light can be emitted through a relatively large surface area, luminous efficiency may be significantly enhanced. However, indium may not be easily incorporated into an active layer during a growth process, and thus, it may be difficult to obtain emissions of long wavelength light.
In general, when InGaN is grown, indium incorporation differs according to crystal planes. In a case of using an m-plane, a non-polar plane, such as a surface of a nanocore, an indium incorporation ratio of the m-plane is lower than that of a c-plane as a polar plane or an r-plane as a semi-polar plane, and thus, it is difficult to form an active layer emitting light having a relatively long wavelength. Also, a defect such as a stacking fault occurs in the active layer due to a difference in lattice constants between the nanocore formed of n-type GaN and the active layer containing indium, degrading efficiency.
Accordingly, a need exists for an LED having reduced structural stress, reduced stacking fault defects and increased indium incorporation in the active layer.